package 测试;

import java.util.HashMap;
import java.util.Map;

public class Demo00001 {
    public static void main(String[] args) {
        Map<String,String> map = new HashMap<>();
        map.put("a","A");
        map.put("b","B");
        map.put("c","C");
        map.put("d","D");
        System.out.println(map);
    }
}
